Plate lifter



E. R. MILLER PLATE LIFTER A May 14, 194,0.

Filed Sept. 28, 1939 mw u, am

h J Nm, Qn mrs Patented May 14, i940 PATENT oFFicE PLATE LIFTER Edgar R. Miller, Chicago, Ill., assigner to F. J. Littell 'Machine Co., Chicago, Ill., a corporation of Illinois Applicationseptember 28, 1939, Serial No. 296,876

4 Claims.

This invention relates to a new and improved plate lifter or the like, and more particularly to a deviceof this character operating by .means of suction created by a uid under pressure.

A plate lifter of this type is of particular utility in handling plates, sheets or shapes formed of metal or other material which is substantially impervious to air and may consequently be lifted and moved by a suction grip. A suction lifter of 1oy this type is useful in handling sheets or plates which because of their shape or size may bedifiicult to move by hand or with mechanical means, such as tongs. This device is also important in its safety advantages in that sheets 15 may be introduced within or removed from a punch or shaping press without inserting the hand or fingers Within the zone of the moving parts. The suctioncups may be located at the end of relatively long. supporting arms so that go the work may be handled well within the ma chine Without endangering the operator.

It is an object of the present inventionpto provide a new and improved plate lifter or the like, of the suction type.

g5 It is a further object to provide a device of thisV character which gives a substantial suction derived from 4the flow of fluid, such as compressed air, under comparatively low pressure.

It is an additional object to provide a plate 3U lifter utilizing the discharge of fluid under pres sure through a Venturi-like orifice to create the desired suction.

It is also an object to provide a construction in which the relationship of the discharge, Venturi and suction oriiices may be readily adjusted.

It is a further object to provide a plate lifter composed of but few and simple parts and adapted for commercial production and use.

Other and further objects will appear as the description proceeds.

I have shown a preferred embodiment of my invention in the accompanying drawing, in which- Figure 1 is an elevation of the lifting device; 5 Figure 2 is a section on an enlarged scale through the suction head body; and

Figure 3 is a plan view of the suction end of the device showing a modied form of oonstruction.

In the drawing, the pistol grip II is provided with the hose connection I2 for receiving compressed air. This grip is provided with a valve controlled passage connecting the hose or similar conductor I2 and the discharge pipe I3. The valve stem I4 is compressed by means of trigger It to open the valve. The valve maybe of any usual construction and need not be further described herein.

The suction head body i6 is supported upon the end of the tubular rod I3. This suction head 5 construction is best shown in Figure 2. The body I6 has an axial passage Il therethrough, this passage being internally threaded, as shown in the drawing. The intake end E8 of the body is provided with a thread adapted to take the 10 end oi the tubular rod passage I3, while the remainder of the body is provided with a uniform thread. The Venturi member ill is threaded into the discharge end of the body I5 and may be retained in adjusted position by the lock nut 2l). The enlarged end 2i oi the member vi9 is shown .to be formed as a hex nut so as to facilitate the adjustment. Since in the use of these devices the plates which are handled thereby are often pushed by means of this end of the suction head, it is preferably hardened so as to stand up under considerable abuse.

The bore through the Venturi member It is provided with an intermediate reduced section section 22, enlarged end sections 23 and 2d, and 25 with gradually tapering sections and 2t joining the end sections and intermediate section. The jet holder 2l is threaded into the bore il of the body it and holds the tubular jet member i223. The jet member 22 has the ltubular passage 29 30 therethrough communicating with the tubular passage through jet holder 2. As shown at 3i, the outer wall of the jet member 23 is tapered adjacent the discharge end of the jet. The ,jet

holder 2l is provided with notches 32 so that it 35 may 'be adjusted in the body by means of a screwdriver. The tubular locking plug 33 is threaded into the body IS and is jaminedup against the jet holder 2l when that is in adjusted position,

to serve as a lock nut and maintain it in such position.

The suction head body I6 oi theform o con struction shown in Figures l and 2 is provided with the lateral extension 3d having a suction bore 35 therein which intersects the axial bore 45 I'I of the suction head body. The nipple 3S is threaded into the bore 35 and holds the plate 3'! against the outer end ofthe lateral extension 34. The suction nipple 38 is-threaded into nipple 35 1 and retains in place the plate 39, which plate serves to hold the rubber suction cup il against plate 3'I. It will be noted that the lateral suction bore 35 is shown as intersecting the axial bore I1 of the body at an intermediate point on the jet tube 28.

The form of construction shown in Figure 3 dffers from that shown in Figures 1 and 2, in that the body 5I), which is supported in the usual way upon the tubular rod I3, is provided with two lateral extensions 5I and 52, each of which supports a suction cup. These suction cups 53 and 54 are connected internally by passages with the central bore Il-insubsta'ntially the same manner as the connection of the single cup shown in Figure 2.

In the operation of the device the pipe or hose I2 is connected to a source o-f air or other fluid under pressure. When the trigger I5 is depressed to open the valve and permit passage of this fluid, it flows through the tubular rod I3, through the locking plug 33, the jet holder 21, the jet 28, and is discharged through the Venturi member IS. As it passes out ofthe `iet and through the Venturi member it causes a substantial suction through the suction nipple 36 and through the tubular opening I in the nipple 38. If the rubber suction cup I0 is placed upon a plate of metal or sheet of any material substantially impervious to air, sumcient suction is created so that very substantial lifting force may be applied to lift the article through the suction attachment.

vThe actual amount of suction will depend upon the pressure of the discharge through the jet 28. The suction also may be varied within considerable limits by adjusting the relationship of the jet to the Venturi member and by adjusting both of them to the lateral suction opening in the suction head body. I have found, however, that it is usually not necessary to change the adjustment of the relationship between the jet and the lateral suction passage. Once the optimum location has been determined, further adjustment because of changes in fluid pressure may be taken care of under normal conditions by slight adjustment of the Venturi member I9.

The structure shown is simple and composed of but few parts. It will be apparent that any of these parts may be removed and replaced without difculty and without requiring special tools. The device is used to move plates upon punch presses or the like, and often when the suction is released by releasing the trigger I5 and cutting off the fluid flow, the plate or other object being handled will not be up against the stops or in exactly the proper position on the machine.v It is therefore, as has been stated, customary for operators to use the end of the device, which in the present construction is the enlarged end 2.I of the Venturi member, to push the work around, so as to bring it up against the stops for the operation of the punch press, drill press or other machine in connection with which the device is used. It will be apparent that this member can be readily replaced when worn or broken by such use or abuse. If the entire Venturi device is hardened the inner Venturi surface will also be less susceptible to wear by any foreign ma- .terial blown through it With the compressed air.

It will be apparent that the size and relation- 2,200,800 ,El l

' through, a suction passage through a lateral Wall of the body intersecting the axial passage, the axial passage being progressively reduced and expanded to one side of the passage intersection, and a reduced discharge nozzle extending across the intersection centrally of the axial passage,

said discharge passage terminating adjacent the progressively reduced portion of the axial passage.

2. A suction lifting device comprising a suction head body having an axial passage therethrough, a suction passage through a lateral wall ofthe body intersecting the axial passage, `a tubular member threaded into the axialv passage on one Side of said suction passage, said member having its opening progressively reduced andvexpanded at an intermediate portion thereof, a second tubular member threaded into the axial passage upon the opposite side of the suction passage, said second member having a reduced tubular portion extending centrally of the axial passage across the intersection of the suction passage therewith, and terminating within the first 'member spaced from the inner wall thereof.

3. A suction lifting device comprising a suction head body having an axial passage therethrough,

a suction passage through a lateral wall of the ond tubular member threaded into the axial passage upon the opposite side of the suction passage, said second member having a reduced tubular portion extending centrally of the axial passage across the intersection of the suction passage therewith, and terminating within the first member spaced from the inner wall thereof at a point Where the size of the opening through the first member has beenv somewhat reduced in size. y

4. A suction lifting device comprising a suction head having an axial passage therethrough, said head having a suction passage intersecting an intermediate portion of the axial passage, the axial passage on one side of the suction passage having substantially a Venturi form, and areduced jet passage extending from the other portion ofthe axial passage across the junction of the axial and suction passages and discharging adjacent the reduced portion of the venturi.

` EDGAR R. MILLER 

